$ { \left[\begin{array}{rr}{4} & {-2} \\ {-2} & {2} \\ {3} & {3}\end{array}\right]+\left[\begin{array}{rr}{2} & {0} \\ {-2} & {-1} \\ {3} & {3}\end{array}\right] = {?} } $
Answer: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{4}+{2} & {-2}+{0} \\ {-2}+{-2} & {2}+{-1} \\ {3}+{3} & {3}+{3}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{6} & {-2} \\ {-4} & {1} \\ {6} & {6}\end{array}\right]}$